VOQL sessions in Beijing and DAL-VOQL joint sessions

Doug Tody dtody at nrao.edu
Fri May 4 10:51:37 PDT 2007

On Fri, 4 May 2007, Francois Ochsenbein wrote:

> I could try to talk about the metadata requirements --
> but the information_schema being something existing almost only in
> SQL server, I don't feel it would be wise to insist on this solution.
> Cheers, francois

Probably the implementation of information_schema is pretty mixed,
although I got the impression that MySQL and PostgreSQL have a pretty
good implementation as well, and possibly DB2 and INFORMIX (but not
Oracle evidently).  And of course SQL Server.

I suggest we consider the issue of an information_schema like
approach, and the issue of whether to use the information_schema
specification directly, as two separate issues.  The key question
is what metadata is required to compose non-trivial queries, as
opposed to discovery/planning via the registry, where only very
limited information is required, and whether these are the same
or distinct.  I just would hate to see TAP crippled by an approach
which can't easily grow to support more sophisticated applications,
and efficient execution of complex queries against large tables.

 	- Doug

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